Lionel Messi and World Cup 2006

The injury that kept Messi from playing for two months at the end of the 2005–06 season jeopardised his presence in the 2006 World Cup. Nevertheless, Messi was selected in the Argentina squad for the tournament on 15 May 2006. He also played in the final match before the World Cup against the Argentine U-20 team for 15 minutes and a friendly match against Angola from the 64th minute. He witnessed Argentina's opening match victory against Ivory Coast from the substitute's bench. In the next match against Serbia and Montenegro, Messi became the youngest player to represent Argentina at a World Cup when he came on as a substitute for Maxi Rodríguez in the 74th minute. He assisted Hernán Crespo's goal within minutes of entering the game and also scored the final goal in the 6–0 victory, making him the youngest scorer in the tournament and the sixth youngest goalscorer in the history of the World Cup. Messi started in Argentina's following 0–0 draw against the Netherlands. In the following game against Mexico, Messi came on as a substitute in the 84th minute, with the score tied at 1–1. He appeared to score a goal, but it was ruled offside with Argentina needing a late goal in extra time to proceed. Coach José Pekerman left Messi on the bench during the quarter-final match against Germany, which they lost 4–2 on a penalty shootout.

Cristiano Ronaldo and World Cup 2006

Ronaldo was the second-highest scorer in FIFA World Cup qualification in the European zone with seven goals, and scored his first World Cup goal against Iran with a penalty kick.

During a quarter-final match against England on 1 July 2006, Ronaldo's United teammate Wayne Rooney was sent off for stamping on Portugal defender Ricardo Carvalho. The English media speculated that Ronaldo had influenced referee Horacio Elizondo's decision by aggressively complaining, after which he was seen in replays winking at the Portuguese bench following Rooney's dismissal. After the match, Ronaldo insisted that Rooney was a friend and that he was not pushing for Rooney to be sent off. On 4 July, Elizondo clarified that the red card was due to Rooney's infraction and not the fracas between Rooney and Ronaldo that followed.

The angry reaction from the English press caused Ronaldo to consider leaving United, and he allegedly told Spanish sports daily Marca that he wished to move to Real Madrid. In response to the speculation, Ferguson sent Portuguese assistant manager Carlos Queiroz to speak to Ronaldo in attempt to change his mind, a sentiment that was shared by Rooney. Ronaldo stayed, and signed his new five-year extension in April 2007.

Ronaldo was booed during Portugal's semi-final defeat to France, and missed out on the competition's Best Young Player award due to a negative e-mail campaign from England fans. Though the online vote only affected the nomination process, FIFA's Technical Study Group awarded the honour to Germany's Lukas Podolski, citing Ronaldo's behaviour as a factor in the decision.